Lighting unit



Jan. 17, 1933. c. E. FERREE ET AL 1,394,533

' LIGHTING UNIT Filed Sept. 17, 1930 Patented Jan. 17, 1933 PATENT OFFICE UNITED STATES CLARENCE ERROL FERREE AND GEBTRUDE RAND FERBEE, OI BALTIMORE, MARYLAND LIGHTING unr'r Application filed September 17, 1930. Serial No. 482,533.

The present invention relates to the com- 10 is possible the glare from the work illuminated.

In the operation of the improved unit, which is the subject of the invention, a portion of the rays are turned upwardly against 15 the ceiling, which acts as a secondary reflector, the light which is reflected in this way being so modified and reduced that it gives illumination of a difluse nature entirely free from glare and at the same time the work is 20 further illuminated by the direct rays from the source of illumination and from the reflector, which direct and reflected rays are in the preferred form of the invention rendered diffuse in an suitable manner as by passing through a t in plate of suitably prepared glassware and are prevented from entering the eye by a specially constructed shield or baflie. A maximum of protection of the eye from glare from the unit and from the work 0 is thus secured with a minimum loss of eifective light.

In the accompanying drawing we have illustrated a lighting unit embodying the'features of our invention in the preferred form.

In the drawing:

Figure 1 is a perspective view of the lighting unit in operative position and fully equipped.

Figure 2 is a bottom plan view of the same.

Figure 3 is a similar view showin the unit equipped with a modified form of afiie.

Referring to the drawing by numerals, each of which is used to indicate the same or similar parts in the different figures, the construction shown comprises a combined direct and indirect reflector 1, which is preferably opaque, but may be translucent to any desirable degree. This reflector has its reflecting surface 2 comprising a peripheral portion or zone 3 upwardly disposed so that the rays of light indicated, for example, at 4, from the source of illumination 5 which come in contact with this upwardly disposed portion or zone 3 of the reflector 1 are pro ected upwardly against the ceiling 6, the reflected portion of the beam being indicated by 4. The lower zone of the reflector at 7 is shown as cylindrical providing a downwardly disposed openingl8 shown as circular, whereby a portion of t e direct rays from the source of illumination 5 indicated by reference character 9 are permitted to be projected downwardly in t e direction of the work and all the rays 10 which come in contact with the zone 7 are at least in the absence of the baflle 11 to be further described, also projected downwardly through the opening 8.

An important feature of the invention relates to the provision in combination with the direct and indirect lighting reflector 1, or a reflector of this general type or any equivalent construction of a baflie corresponding to the baflie 11, controlling the rays of light projected from the reflecting surface at 7 above and surrounding the opening 8 and the rays 9 projected directly from the source of illumination, thereby shielding the eye from the glare which might result from these rays but permitting the work to be illuminated by direct rays from the source of illumination and rays reflected from the zone 7.

While the construction shown, particularly as to the opening 8 and the provision of a refleeting surface surrounding the opening 8 is the preferred form, this form and construction may be considerably varied as to the configuration of the opening 8 and the shape of the zone 7, any shape and configuration of these elements which is suitable for the purposes in hand being regarded as an obvious variation of the construction shown.

Immediately overlying the baifle, the drawing shows a dilfusing member 12, which may be in the form of a plate of ground glass or flashed glass. This is preferably of high transmission properties and has for its purpose the di'fl'usion to a predetermined and to any desired degree of the downwardly projected intense direct rays and those which are reflected from the zone 7 and hence through the baflle. I

In the preferred form of the invention, the baflle consists of partitions 14, Figures 1 and 2. While the exact dimensions and arrangement are not of controlling importance, the preferred arrangement is of interest. In the drayving the baflle is shown as consisting of two series of substantially vertical partitions 14 extending across the opening 8 at right angles to each other, the partitions extending in each direction being preferably parallel and spaced apart by about two inches and being approximately two and one half inches wide in a vertical direction dividing the opening into a series of downwardly extending passages 12 through which the vertical or substantially vertical light rays are projected u on the work, the sharply inclined rays indicated by reference character 16 being elimi nated by the baffle the partitions forming which are preferably painted or coated with dark lustreless material to kill the brightness of the rays which come in contact with it. In this way the vertical rays and those approaching the vertical which pass through the openings 15 are projected directly upon the work without interference. These would not come in contact with the eye unless the observer looked directly upward from beneath which is not according to working con ditions, being of unusual occurrence, the eye being fully protected by the operation of the bafile which eliminates the sharply inclined rays which under ordinary working conditions would come in contact with the eye.

Figure 3 illustrates a slightly difierent secondary form of baflle comprising vertical partitions 20 which are radially disposed, and vertical partitions 21 arranged in the form of concentric circles providing vertically disposed openings or passages 22 having an effeet which is similar to that of the passages 15 in Figures 1 and 2. r

The operation of the lighting unit has been fully described in connection with its structure.

i We have thus described specifically and in detail a lighting unit embodying the features of our invention in the preferred form in order that the manner of constructing, operating and using the same and practicing and applying the invention may be fully understood, however, the construction of the apparatus and of the arrangement of the same may be widely varied within the scope of the invention, the terms being used in a descriptive rather than in a limiting sense, the scope of the invention being defined in the claims' What we claim as new and desire to secure by Letters Patent is:

1. The combination 1n a lighting unit having a source of illumination, of a reflector adapted to project a portion of the light therefrom toward the ceiling and apertured nation and laterally disposed reflecting means surrounding said opening, a light bafile shielding the eye from the glare of the sharply inclined rays from said opening but permitting the downwardly directed rays to pass, the said bafile being composed of a series of downwardly disposed passages having substantially vertical side walls.

3. The combination in a lighting unit having a source of illumination of a reflector adapted to project a proportion of the rays upwardly against the ceiling for indirect lighting and formed with a downwardly disposed opening beneath the source of illumination and laterally disposed reflecting means surrounding said opening, a light baffie shielding the eye from the glare of the sharply inclined rays from said opening but permitting the more nearly vertical rays to pass, the said bafile being composed of a series of passages having substantially vertical side walls .with non-lustrous surfaces and a horizontal difiusing plate in the path of the rays passing through said opening.

Signed at New York, this 21st day of August 1930.

CLARENCE ERROL FERREE. GERTRUDE RAND FERREE. 

